Abdominal: Relating to the abdomen, the belly, that part of the body that contains all of the structures between the chest and the pelvis. The abdomen is separated anatomically from the chest by the diaphragm, the powerful muscle spanning the body cavity below the lungs. See the entire definition of Abdominal
Abdominal pain: Pain in the belly (the abdomen). Abdominal pain can come from conditions affecting a variety of organs. The abdomen is an anatomical area that is bounded by the lower margin of the ribs above, the pelvic bone (pubic ramus) below, and the flanks on each side. Although abdominal pain can arise from the tissues of the abdominal wall that surround the abdominal cavity (the skin and abdominal wall muscles), the term abdominal pain generally is used to describe pain originating from organs within the abdominal cavity (from beneath the skin and muscles). These organs include the stomach, small intestine, colon, liver, gallbladder, and pancreas. See the entire definition of Abdominal pain
Allergic reaction: The hypersensitive response of the immune system of an allergic individual to a substance. See the entire definition of Allergic reaction
Alprazolam: A benzodiazepine sedative that causes dose-related depression of the central nervous system. Alprazolam is useful in treating anxiety, panic attacks, insomnia, and muscle spasms. The brand name is Xanax. A generic version is available.
Amitriptyline: An antidepressant medication. In some patients with depression, abnormal levels of brain chemicals called neurotransmitters may relate to the depression. Amitriptyline elevates mood by raising the level of neurotransmitters in brain tissue. Amitriptyline is also a sedative that is useful for depressed patients with insomnia, restlessness, and nervousness. It is sometimes used to treat fibromyalgia and symptoms related to chronic pain. Brand names are Elavil and Endep. A generic version is available.
Anti-: Prefix generally meaning "against, opposite or opposing, and contrary." In medicine, anti- often connotes "counteracting or effective against" as in antibacterial, anti-infective, and antiviral. Sometimes medical terms containing anti- take on new meanings as has occurred with antibiotic and antibody. As a prefix, anti- may be shortened to ant- as in antacid. "Anti" is the Greek word for "against."
Antidepressants: Anything, and especially a drug, used to prevent or treat depression. See the entire definition of Antidepressants
Antiviral: An agent that kills a virus or that suppresses its ability to replicate and, hence, inhibits its capability to multiply and reproduce. See the entire definition of Antiviral
Anxiety: A feeling of apprehension and fear characterized by physical symptoms such as palpitations, sweating, and feelings of stress. Anxiety disorders are serious medical illnesses that affect approximately 19 million American adults. These disorders fill people's lives with overwhelming anxiety and fear. Unlike the relatively mild, brief anxiety caused by a stressful event such as a business presentation or a first date, anxiety disorders are chronic, relentless, and can grow progressively worse if not treated. See the entire definition of Anxiety
Artery: A vessel that carries blood high in oxygen content away from the heart to the farthest reaches of the body. Since blood in arteries is usually full of oxygen, the hemoglobin in the red blood cells is oxygenated. The resultant form of hemoglobin (oxyhemoglobin) is what makes arterial blood look bright red. See the entire definition of Artery
Atorvastatin: A medication that lowers the level of cholesterol in the blood. Atorvastatin is a statin drug. All statins prevent the production of cholesterol in the liver by blocking the enzyme that makes cholesterol, HMGCoA reductase. They lower total blood cholesterol as well as low-density lipoprotein (LDL) cholesterol levels. Lowering LDL cholesterol levels retards progression and may even reverse coronary artery disease. Unlike the other statins, atorvastatin can also reduce the concentration of triglycerides in the blood. (High blood concentrations of triglycerides have been associated with coronary artery disease.) The brand name of atorvastin is Lipitor.
Birth control: Birth control is the use of any practices, methods, or devices to prevent pregnancy from occurring in a sexually active woman. Also referred to as family planning, pregnancy prevention, fertility control, or contraception; birth control methods are designed either to prevent fertilization of an egg or implantation of a fertilized egg in the uterus. See the entire definition of Birth control
Blood pressure: The blood pressure is the pressure of the blood within the arteries. It is produced primarily by the contraction of the heart muscle. It's measurement is recorded by two numbers. The first (systolic pressure) is measured after the heart contracts and is highest. The second (diastolic pressure) is measured before the heart contracts and lowest. A blood pressure cuff is used to measure the pressure. Elevation of blood pressure is called "hypertension".
Breast milk: Milk from the breast. Human milk contains a balance of nutrients that closely matches infant requirements for brain development, growth and a healthy immune system. Human milk also contains immunologic agents and other compounds that act against viruses, bacteria, and parasites. Since an infant's immune system is not fully developed until age 2, human milk provides a distinct advantage over formula. See the entire definition of Breast milk
Breathing: The process of respiration, during which air is inhaled into the lungs through the mouth or nose due to muscle contraction, and then exhaled due to muscle relaxation.
Calcium: A mineral found mainly in the hard part of bones, where it is stored. Calcium is added to bones by cells called osteoblasts and is removed from bones by cells called osteoclasts. Calcium is essential for healthy bones. It is also important for muscle contraction, heart action, nervous system maintenance, and normal blood clotting. Food sources of calcium include dairy foods, some leafy green vegetables such as broccoli and collards, canned salmon, clams, oysters, calcium-fortified foods, and tofu. According to the National Academy of Sciences, adequate intake of calcium is 1,200 milligrams a day (four glasses of milk) for men and women 51 and older, 1,000 milligrams a day for adults 19 through 50, and 1,300 milligrams a day for children 9 through 18. The upper limit for calcium intake is 2.5 grams daily.
Learn more about calcium with evidence-based information on RxList.
Cell: The basic structural and functional unit in people and all living things. Each cell is a small container of chemicals and water wrapped in a membrane. See the entire definition of Cell
Cholesterol: The most common type of steroid in the body, cholesterol has gotten something of a bad name. However, cholesterol is a critically important molecule. See the entire definition of Cholesterol
Colchicine: A substance found in a plant that is used in clinical medicine for the treatment of gouty arthritis and in the laboratory to arrest cells during cell division (by disrupting the spindle) so their chromosomes can be visualized. The name colchicine is from the Greek kolchikon meaning autumn crocus or meadow saffron, the plant from which colchicine was originally isolated.
Coronary artery disease: A major cause of illness and death, coronary artery disease (CAD) begins when hard cholesterol substances (plaques) are deposited within a coronary artery. See the entire definition of Coronary artery disease
Cough: A rapid expulsion of air from the lungs typically in order to clear the lung airways of fluids, mucus, or material. Also called tussis.
Cure:1. To heal, to make well, to restore to good health. Cures are easy to claim and, all too often, difficult to confirm. 2. A time without recurrence of a disease so that the risk of recurrence is small, as in the 5-year cure rate for malignant melanoma. 3. Particularly in the past, a course of treatment. For example, take a cure at a spa. See the entire definition of Cure
Diabetes: Refers to diabetes mellitus or, less often, to diabetes insipidus. Diabetes mellitus and diabetes insipidus share the name "diabetes" because they are both conditions characterized by excessive urination (polyuria). See the entire definition of Diabetes
Diarrhea: A familiar phenomenon with unusually frequent or unusually liquid bowel movements, excessive watery evacuations of fecal material. The opposite of constipation. The word "diarrhea" with its odd spelling is a near steal from the Greek "diarrhoia" meaning "a flowing through." Plato and Aristotle may have had diarrhoia while today we have diarrhea. There are myriad infectious and noninfectious causes of diarrhea. See the entire definition of Diarrhea
Dizziness: Painless head discomfort with many possible causes including disturbances of vision, the brain, balance (vestibular) system of the inner ear, and gastrointestinal system. Dizziness is a medically indistinct term which laypersons use to describe a variety of conditions ranging from lightheadedness, unsteadiness to vertigo. See the entire definition of Dizziness
Drain: A device for removing fluid from a cavity or wound. A drain is typically a tube or wick. As a verb, to allow fluid to be released from a confined area.
Erectile dysfunction: A common men's health problem characterized by the consistent inability to sustain an erection sufficient for sexual intercourse or the inability to achieve ejaculation, or both. Impotence can vary. It can involve a total inability to achieve an erection or ejaculation, an inconsistent ability to do so, or a tendency to sustain only very brief erections. Erectile dysfunction is also called impotence, See the entire definition of Erectile dysfunction
Ergot: Ergot could be called a "cereal killer" for it comes from cereals such as rye and wheat and is quite capable of killing someone. A fungus (Claviceps purpurea) that contaminates rye and wheat produces substances (alkaloids) termed ergotamines. See the entire definition of Ergot
Erythromycin:Erythromycin is a common antibiotic for treating bacterial infection. Sold under many brand names, including EES, Erycin and Erythromia.
Fatigue: A condition characterized by a lessened capacity for work and reduced efficiency of accomplishment, usually accompanied by a feeling of weariness and tiredness. Fatigue can be acute and come on suddenly or chronic and persist. See the entire definition of Fatigue
FDA: The Food and Drug Administration, an agency within the U.S. Public Health Service, which is a part of the Department of Health and Human Services. See the entire definition of FDA
Fever: Although a fever technically is any body temperature above the normal of 98.6 degrees F. (37 degrees C.), in practice a person is usually not considered to have a significant fever until the temperature is above 100.4 degrees F (38 degrees C.). See the entire definition of Fever
Flush: (1) A redness of the skin, typically over the cheeks or neck. A flush is usually temporary and brought on by excitement, exercise, fever, or embarrassment. Flushing is an involuntary (uncontrollable) response of the nervous system leading to widening of the capillaries of the involved skin. Also referred to as a blush (or, as a verb, to blush). Flushing may also be caused by medications or other substances that cause widening of the capillaries, such as niacin. (2) Flush also means to wash out a wound or body area.
Garlic: A perennial herb of the lily family cultivated for its pungent, edible bulbs. Garlic has been used with the intention of lowering blood pressure and cholesterol. See the entire definition of Garlic
Generic:1. The chemical name of a drug. 2. A term referring to the chemical makeup of a drug rather than to the advertised brand name under which the drug may be sold. 3.A term referring to any drug marketed under its chemical name without advertising.
Headache: A pain in the head with the pain being above the eyes or the ears, behind the head (occipital), or in the back of the upper neck. Headache, like chest pain or back ache, has many causes. See the entire definition of Headache
Heart: The muscle that pumps blood received from veins into arteries throughout the body. It is positioned in the chest behind the sternum (breastbone; in front of the trachea, esophagus, and aorta; and above the diaphragm muscle that separates the chest and abdominal cavities. The normal heart is about the size of a closed fist, and weighs about 10.5 ounces. It is cone-shaped, with the point of the cone pointing down to the left. Two-thirds of the heart lies in the left side of the chest with the balance in the right chest. See the entire definition of Heart
Heart attack: The death of heart muscle due to the loss of blood supply. The loss of blood supply is usually caused by a complete blockage of a coronary artery, one of the arteries that supplies blood to the heart muscle. Death of the heart muscle, in turn, causes chest pain and electrical instability of the heart muscle tissue. See the entire definition of Heart attack
Hemophilia: A group of inherited bleeding disorders in which the ability of blood to clot is impaired. See: Hemophilia A; Hemophilia B.
High blood pressure: Also known as hypertension, high blood pressure is, by definition, a repeatedly elevated blood pressure exceeding 140 over 90 mmHg -- a systolic pressure above 140 with a diastolic pressure above 90. See the entire definition of High blood pressure
HIV: Acronym for the Human Immunodeficiency Virus, the cause of AIDS (acquired immunodeficiency syndrome). HIV has also been called the human lymphotropic virus type III, the lymphadenopathy-associated virus and the lymphadenopathy virus. No matter what name is applied, it is a retrovirus. (A retrovirus has an RNA genome and a reverse transcriptase enzyme. Using the reverse transcriptase, the virus uses its RNA as a template for making complementary DNA which can integrate into the DNA of the host organism). See the entire definition of HIV
Human immunodeficiency virus: HIV, the cause of AIDS. HIV has also been called the human lymphotropic virus type III, the lymphadenopathy-associated virus and the lymphadenopathy virus. No matter what name is applied, it is a retrovirus. (A retrovirus has an RNA genome and a reverse transcriptase enzyme. Using the reverse transcriptase, the virus uses its RNA as a template for making complementary DNA which can integrate into the DNA of the host organism). Although the American research Robert Gallo at the National Institutes of Health believed he was the first to find HIV, it is now generally accepted that the French physician Luc Montagnier (1932-) and his team at the Pasteur Institute discovered HIV in 1983- 84.
Hypertension: High blood pressure, defined as a repeatedly elevated blood pressure exceeding 140 over 90 mmHg -- a systolic pressure above 140 with a diastolic pressure above 90. See the entire definition of Hypertension
Immune: Protected against infection. The Latin immunis means free, exempt.
Immune system: A complex system that is responsible for distinguishing us from everything foreign to us, and for protecting us against infections and foreign substances. The immune system works to seek and kill invaders. See the entire definition of Immune system
Immunodeficiency: Inability to mount a normal immune response. Immunodeficiency can be due to a genetic disease or acquired as in AIDS due to HIV.
Infection: The growth of a parasitic organism within the body. (A parasitic organism is one that lives on or in another organism and draws its nourishment therefrom.) A person with an infection has another organism (a "germ") growing within him, drawing its nourishment from the person. See the entire definition of Infection
Itching: An uncomfortable sensation in the skin that feels as if something is crawling on the skin or in the skin, and makes the person want to scratch the affected area. See the entire definition of Itching
Kidney: One of a pair of organs located in the right and left side of the abdomen which clear "poisons" from the blood, regulate acid concentration and maintain water balance in the body by excreting urine. The kidneys are part of the urinary tract. The urine then passes through connecting tubes called "ureters" into the bladder. The bladder stores the urine until it is released during urination.
Laboratory: A place for doing tests and research procedures and preparing chemicals, etc. Although "laboratory" looks very like the Latin "laboratorium" (a place to labor, a work place), the word "laboratory" came from the Latin "elaborare" (to work out, as a problem, and with great pains), as evidenced by the Old English spelling "elaboratory" designating "a place where learned effort was applied to the solution of scientific problems."
Lipid: Another word for "fat." (Please see the various meanings of Fat.) A lipid is more formally defined as a substance such as a fat, oil or wax that dissolves in alcohol but not in water. Lipids contain carbon, hydrogen and oxygen but have far less oxygen proportionally than carbohydrates. See the entire definition of Lipid
Liver: An organ in the upper abdomen that aids in digestion and removes waste products and worn-out cells from the blood. The liver is the largest solid organ in the body. The liver weighs about three and a half pounds (1.6 kilograms). It measures about 8 inches (20 cm) horizontally (across) and 6.5 inches (17 cm) vertically (down) and is 4.5 inches (12 cm) thick.
Liver disease: Liver disease refers to any disorder of the liver. The liver is a large organ in the upper right abdomen that aids in digestion and removes waste products from the blood. See the entire definition of Liver disease
Medical history:1. In clinical medicine, the patient's past and present which may contain clues bearing on their health past, present, and future. The medical history, being an account of all medical events and problems a person has experienced, including psychiatric illness, is especially helpful when a differential diagnosis is needed. 2. The history of medicine.
MedicAlert: A nonprofit emergency medical information service, known for its MedicAlert jewelry, particularly the bracelet, and its 24-hour emergency response center. See the entire definition of MedicAlert
Methadone: A synthetic opiate. The most common medical use for methadone is as a legal substitute for heroin in treatment programs for drug addiction. It is usually administered to participating addicts daily in the form of a green, tasteless liquid at a drug treatment clinic. See also: Methadone treatment program.
Mouth:1. The upper opening of the digestive tract, beginning with the lips and containing the teeth, gums, and tongue. Foodstuffs are broken down mechanically in the mouth by chewing and saliva is added as a lubricant. Saliva contains amylase, an enzyme that digests starch. 2. Any opening or aperture in the body. The mouth in both senses of the word is also called the os, the Latin word for an opening, or mouth. The o in os is pronounced as in hope. The genitive form of os is oris from which comes the word oral.
Nausea:Nausea, is the urge to vomit. It can be brought by many causes including, systemic illnesses, such as influenza, medications, pain, and inner ear disease. When nausea and/or vomiting are persistent, or when they are accompanied by other severe symptoms such as abdominal pain, jaundice, fever, or bleeding, a physician should be consulted.
Pain: An unpleasant sensation that can range from mild, localized discomfort to agony. Pain has both physical and emotional components. The physical part of pain results from nerve stimulation. Pain may be contained to a discrete area, as in an injury, or it can be more diffuse, as in disorders like fibromyalgia. Pain is mediated by specific nerve fibers that carry the pain impulses to the brain where their conscious appreciation may be modified by many factors. See the entire definition of Pain
Pharmacist: A professional who fills prescriptions, and in the case of a compounding pharmacist, makes them. Pharmacists are familiar with medication ingredients, interactions, cautions, and hints. See the entire definition of Pharmacist
Poison: Any substance that can cause severe distress or death if ingested, breathed in, or absorbed through the skin. Many substances that normally cause no problems, including water and most vitamins, can be poisonous if taken in too large of a quantity. Poison treatment depends on the substance: if there are treatment instructions on the substance's container and you are sure it contained no other item, follow those directions immediately. Always contact your nearest Poison Control Center if you are concerned about possible poison ingestion.
Poison Control Center: Special information centers set up to inform Americans about how to respond to potential poisoning. These centers maintain a database of poisons and appropriate emergency treatment. The Poison Control Center in your area should be listed with other community service numbers in the front of your telephone book, and can also be reached immediately through any telephone operator. See the entire definition of Poison Control Center
Pregnancy: The state of carrying a developing embryo or fetus within the female body. This condition can be indicated by positive results on an over-the-counter urine test, and confirmed through a blood test, ultrasound, detection of fetal heartbeat, or an X-ray. Pregnancy lasts for about nine months, measured from the date of the woman's last menstrual period (LMP). It is conventionally divided into three trimesters, each roughly three months long. See the entire definition of Pregnancy
Prescription: A physician's order for the preparation and administration of a drug or device for a patient. A prescription has several parts. They include the superscription or heading with the symbol "R" or "Rx", which stands for the word recipe (meaning, in Latin, to take); the inscription, which contains the names and quantities of the ingredients; the subscription or directions for compounding the drug; and the signature which is often preceded by the sign "s" standing for signa (Latin for mark), giving the directions to be marked on the container.
Protease: An enzyme that can split a protein into peptides (from which the protein was originally created).
Protease inhibitor: One of a class of anti-HIV drugs designed to inhibit the enzyme protease and thereby interfere with virus replication. See the entire definition of Protease inhibitor
Pulmonary: Having to do with the lungs. (The word comes from the Latin pulmo for lung).
Pulmonary hypertension: High blood pressure in the pulmonary artery that conveys blood from the right ventricle to the lungs. The pressure in the pulmonary artery is normally low compared to that in the aorta. Pulmonary hypertension can irrevocably damage the lungs and cause failure of the right ventricle. See the entire definition of Pulmonary hypertension
Rash: Breaking out (eruption) of the skin. Medically, a rash is referred to as an exanthem.
Seizure: Uncontrolled electrical activity in the brain, which may produce a physical convulsion, minor physical signs, thought disturbances, or a combination of symptoms. See the entire definition of Seizure
Shortness of breath: Difficulty in breathing. Medically referred to as dyspnea. Shortness of breath can be caused by respiratory (breathing passages and lungs) or circulatory (heart and blood vessels) conditions. See also dyspnea.
St John's wort: A flowering plant, Hypericum perforatum, also known as Perforate St John's wort, that has long been believed to have medicinal qualities. See the entire definition of St John's wort
Stomach:1. The sac-shaped digestive organ that is located in the upper abdomen, under the ribs. The upper part of the stomach connects to the esophagus, and the lower part leads into the small intestine. See the entire definition of Stomach
Sweating: The act of secreting fluid from the skin by the sweat (sudoriferous) glands. These are small tubular glands situated within and under the skin (in the subcutaneous tissue). They discharge by tiny openings in the surface of the skin. See the entire definition of Sweating
Tacrolimus: A drug that suppresses the immune system and prevents transplant rejection. The drug acts by inhibiting the activation of T cells. See the entire definition of Tacrolimus
Taste: Taste belongs to our chemical sensing system, or the chemosenses. The complicated process of tasting begins when molecules released by the substances stimulate special cells in the mouth or throat. These special sensory cells transmit messages through nerves to the brain where specific tastes are identified. See the entire definition of Taste
Urine: Liquid waste. The urine is a clear, transparent fluid. It normally has an amber color. The average amount of urine excreted in 24 hours is from 40 to 60 ounces (about 1,200 cubic centimeters). Chemically, the urine is mainly an aqueous (watery) solution of salt (sodium chloride) and substances called urea and uric acid. Normally, it contains about 960 parts of water to 40 parts of solid matter. Abnormally, it may contain sugar (in diabetes), albumen (a protein) (as in some forms of kidney disease), bile pigments (as in jaundice), or abnormal quantities of one or another of its normal components.
Virus: A microorganism smaller than a bacteria, which cannot grow or reproduce apart from a living cell. A virus invades living cells and uses their chemical machinery to keep itself alive and to replicate itself. It may reproduce with fidelity or with errors (mutations)-this ability to mutate is responsible for the ability of some viruses to change slightly in each infected person, making treatment more difficult. See the entire definition of Virus
Warfarin: An anticoagulant drug (brand names: Coumarin, Panwarfin, Sofarin) taken to prevent the blood from clotting and to treat blood clots and overly thick blood. Warfarin is also used to reduce the risk of clots causing strokes or heart attacks. See the entire definition of Warfarin
Weight loss: Weight loss is a decrease in body weight resulting from either voluntary (diet, exercise) or involuntary (illness) circumstances. Most instances of weight loss arise due to the loss of body fat, but in cases of extreme or severe weight loss, protein and other substances in the body can also be depleted. Examples of involuntary weight loss include the weight loss associated with cancer, malabsorption (such as from chronic diarrheal illnesses ), and chronic inflammation (such as with rheumatoid arthritis).
White blood cell: One of the cells the body makes to help fight infections. There are several types of white blood cells (leukocytes). The two most common types are the lymphocytes and neutrophils (also called polymorphonuclear leukocytes, PMNs, or "polys"). See the entire definition of White blood cell
HIV (human immunodeficiency virus) is the cause of AIDS (acquired immunodeficiency syndrome). HIV is a type of virus called a retrovirus, which infects humans when it comes in contact with a break in the skin or tissues such as those that line the vagina, anal area, mouth, or eyes.
What is the history of HIV, and when was HIV discovered?
The history of the human immunodeficiency virus (HIV) and acquired immunodeficiency syndrome (AIDS) dates back to 1981, when
homosexual men with symptoms of a disease that now are considered typical of AIDS were first described in Los Angeles and New York. The men had an unusual type of lung infection (pneumonia) called
Pneumocystis carinii (now known as
Pneumocystis jiroveci)
pneumonia (PCP) and rare skin tumors called Kaposi's sarcomas. The patients were
noted to have a severe reduction in a type of cell in the blood (CD4 cells) that is an
important part of the immune system. These cells, often referred to as
T cells, help
the body fight infections. Shortly thereafter, this disease was recognized
throughout the United States, Western Europe, and Africa. In 1983, researchers
in the United States and France described the virus that causes AIDS, now known
as HIV, belonging to t...